The Genome Of Dendrobium Officinale Illuminates Biology Of The Important Traditional Chinese Orchid Herb

Dendrobium officinale Kimura et Migo is perennial epiphytic orchid herb whichhas both ornamental value and broad range of therapeutic effects,and has been knownas “the top one of the most famous nine herbs in China”.In this paper, the material isYunnan Pu’er D. officinale. We report a high-quality genome draft(contigN50=25.1kb，scaffoldN50=76.4kb)by combining the second generationIllumina Hiseq2000and the third generation PacBio sequencing technologies,thetotal amount of sequencing Covers more than94%of D. officinale genomesequence, the function annotates97.56%of D. officinale protein-coding genes.We found orchids have complete inflorescence gene set and have some specificinflorescence genes. We observed obvious gene expansion in gene families related tofungus symbiosis and drought resistance. We analyzed biosynthesis pathways ofmedicinal components of D. officinale, and found extensive duplication of SPS andSusy genes which are related to polysaccharides generation, and that pathway ofD. officinale alkaloid synthesis could be extended to generation of16-epivellosimine.The D.officinale genome assembly demonstrates a new approach decipheringlarge complex genomes,the endophytes and the technology of tissue culture andrapid multiplication of D.officinale are also studied further，it will also facilitatefuture research on the evolution of Orchidaceae plants, the study of medicinalcomponents,the construction of D.officinale Fingerprints and potential geneticbreeding of the dendrobe.